Lateral-carrier-transport characteristics in InAs/GaAs quantum-dot (QD) hetero structures has been studied in depth by photoluminescence spectroscopy. Anomalous temperature-dependent phenomena, including spectral width, emission energy, and quenching behaviors, were attributed to carrier-thermalization processes. Increased temperatures facilitated the photoexcited carriers to redistribute in the heterodot system. Carrier redistrubution led to not only the linewith shrinkages, but also the emission redshifts for the excited- and ground-state transitions in QD ensembles. Plan-view transmission electron microscopy also showed the growth-interruption effect on the dot formation. It was found that the longer interruption time improved the dot-size uniformity. (C) 2004 American Vacuum Society.